Scottish Health Survey – telephone survey – August/September 2020: technical report

1.1 Introduction

1.1.1 The Scottish Health Survey series

The Scottish Health Survey (SHeS) series was established in 1995 to provide data about the health of the population living in private households in Scotland. It was repeated in 1998 and 2003 and has been carried out annually since 2008.

The 2018-2021 surveys are being conducted by ScotCen Social Research in collaboration with the Office for National statistics (ONS), the Social and Public Health Sciences Unit (MRC/CSO SPHSU) at the University of Glasgow, the Centre for Population Health Sciences at the University of Edinburgh and the Public Health Nutrition Research Group at the University of Aberdeen^[1].

1.1.2 The SHeS 2020 Telephone Survey

The COVID-19 pandemic resulted in fieldwork for SHeS 2020 (the sixteenth face-to-face survey in the series) being suspended in March 2020. The decision was taken to instead collect data for some of the key measures from SHeS via a telephone survey. Potential participants aged 16 and over were contacted by letter and asked to opt-in to taking part in an interview conducted over the phone.

The telephone survey methods differed from those used in the SHeS series and while the survey includes many questions and key indicators from the face-to-face surveys, the change in mode of administration, along with the different approach to sampling, is likely to have impacted the responses received and thus comparability with the previous SHeS data. See sections 1.1.4 and 1.2 for more information.

The purpose of the SHeS telephone survey was to provide information at national level about the health of the population and the ways in which lifestyle factors are associated with health during the developing COVID-19 pandemic This level of information is not available from administrative or operational databases, as hospitals and GPs are not able to collect detailed information about peoples’ lifestyles and health- related behaviours. In addition, it is crucial that the Scottish Government has information about the health of the population, including people who do not access health services regularly, particularly against the backdrop of a pandemic.

1.1.3 The SHeS 2020 telephone survey report

The SHeS 2020 telephone survey was designed to provide data at national level about the adult population living in private households in Scotland during the months of August and September 2020. Due to the testing of a new methodology for the SHeS survey (already a well-established survey programme) within the context of the COVID-19 pandemic, the survey results in Volume 1 are presented as experimental statistics. This means that the survey reported upon was in a testing phase and that users should be aware of the mode differences and potential impact on results (see section 1.1.4 for more detail).

The 2020 telephone survey report consists of two volumes, published as a set under ‘The Scottish Health Survey 2020 - Telephone Survey’. Volume 1 presents results for adults on a variety of health topics. This report (Volume 2) provides methodological information and survey documentation. Both volumes are available on the Scottish Government’s website (https://www.gov.scot/collections/scottish-health-survey)

1.1.4 Comparisons with previous surveys in the SHeS series

The SHeS 2020 telephone survey was intended to provide a snapshot of the health of Scotland’s population, both physical and mental, over a specified timescale (August and September 2020) within the period of COVID-19 pandemic. The SHeS 2020 telephone survey methods differs from those used on other SHeS surveys in the series and while the survey includes many questions and key indicators from the face-to-face SHeS surveys, the change in survey mode, along with the different approach to sampling, may have impacted the responses received and so affect comparability with the previous SHeS data. It is advised that this report is viewed as a standalone report of data collected during a specific period in time and the approach as experimental to inform potential future approaches while the COVID-19 pandemic is ongoing.

Mode effects

For the 2020 telephone survey, all participant information was collected by the interviewers during the interview. This difference from the usual SHeS face to face, self-complete and objective modes of administration may have affected responses in a number of ways:

• With less opportunity for interviewers to build up a rapport than in a face-to-face situation, participants may be less inclined to reveal sensitive information without fear of disclosure^[2].
  • This is usually mitigated against by including these topics in a self-completion format further enabling participants to answer honestly.
  • It is therefore estimated that there may be some under-reporting of sensitive information, such as long-term conditions, symptoms of anxiety and depression, suicide attempts and poor mental health or poor mental wellbeing.
• There may be a greater degree of social-desirability bias² (where some participants may wish to demonstrate behaviour they feel is likely to be perceived as healthy or ‘acceptable’) than in face to face mode in response to certain questions such as consumption of unhealthy foods, alcohol consumption smoking behaviour and physical activity.
  • There is a greater likelihood of a difference where questions have been moved from self-completion to telephone interviewing including food insecurity, loneliness, mental wellbeing, and social capital, as well as smoking and alcohol consumption for 16-19 year olds which is usually asked as via a self-completion approach.
• For general health, there is potential for a positivity bias, whereby people may over-report how well they feel.
• The use of self-reported measurements for height and weight, rather than the usual objective measurements obtained by interviewers could potentially be expected to lead to an under-reporting of overweight and obesity (see 1.9.5 ‘Chapter 4: Diet and Obesity’ for more information).
• There is a risk of “satisficing” (participants giving the minimum information required to move on through the survey quickly). This can also occur using a face-to-face approach but there is potentially more of a risk using a telephone mode.
  • This risk is greatest when questions are complex and not easy to follow or where the participant is asked to do some sort of calculation, such as to give an average amount. Areas that may have been affected include anxiety and depression, diet, physical activity, alcohol consumption and smoking.
  • Questions with a high number of possible responses may also prove more difficult to answer. This includes the question on treatment for asthma.
  • Such questions are being reviewed for any future SHeS telephone surveying to mitigate as far as possible against this risk.

Timing of data collection

The telephone survey took place during the months of August and September, rather than across the whole of 2020. At the time of data collection, easing of restrictions related to time outside of the home, social interactions and businesses that could open had been introduced which included those previously advised to shield being told they no longer had to^[3].

The time of year, as well as the general context of the COVID-19 pandemic, may have affected responses in a number of ways (both positive and negative impacts) that it is not possible to determine from the survey such as on:

• Perceptions of general health, including among those who have not been diagnosed with or suspect they have had the virus and those with long-term health conditions.
• Mental health and wellbeing, for example, increased anxiety or mental health impacts on individuals with long-term health conditions (irrespective of whether they have been advised to shield or not), potential impacts on loneliness etc.
• Specific health-related behaviours, adopting more positive or less beneficial behaviours related to physical activity, diet, alcohol consumption and smoking, which may vary for individuals throughout the pandemic.

The questionnaire

The survey was shortened for the telephone to minimise the burden on participants. Some questions were asked without the follow-up questions that usually accompany them, thus requiring some variables used in reporting to be derived differently from previous years. See section 1.9 ‘Methods and Definitions’ for more detail on specific topics within the telephone survey.

1.1.5 Access to SHeS data

Data from the SHeS 2020 telephone survey will be deposited at the UK Data Service. Datasets from earlier years in the series are also deposited here (www.ukdataservice.ac.uk).